Journal of Physics & Astronomy

S. Mackowski ¹

Affiliations
1 Journal of Physics and Astronomy, GB

Abstract

A summary of current knowledge of solar activity's long-term behaviour on a multi-millennial timescale, as rebuilt using the indirect proxy method, is presented here. The notion of solar activity is addressed, as well as an overview of the particular indices that are used to quantify various elements of changing solar activity, with a focus on sunspot number. Over long periods, only indirect proxies, such as the cosmogenic isotopes ¹⁴C and ¹⁰Be in natural stratified archives, can be used to derive quantitative information on previous solar activity (e.g., tree rings or ice cores).

Keywords

Solar Variability, Adiabatic Equilibrium, Galactic Cosmic Rays.

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S. Mackowski ¹

Affiliations
1 Journal of Physics and Astronomy, GB

Abstract

No Abstract.

Keywords

No Keywords.

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S. Mackowski ¹

Affiliations
1 S. Mackowski, Executive Manager, Journal of Physics and Astronomy, GB

Abstract

We look at first-order perturbations on homogeneous and hypersurface orthogonal LRS class II spacetimes that are gravitational, electromagnetic, and plasma-related. The examined backgrounds' anisotropy allows us to add a nonzero magnetic field up to the zeroth order. Due to this inclusion, we discover intriguing interactions between the electromagnetic and gravitational variables in the perturbations that are already of the first order. The Ricci identities, Bianchi identities, Maxwell's equations, Einstein's field equations, particle conservation, and an energy-momentum conservation method for the plasma components are all used to get the equations regulating these perturbations. The analyzed quantities and equations are decomposed with regard to the preferred directions on a 1 + 1 + 2 covariant split of space-time. The system is then reduced to a set of ordinary differential equations in time and certain constraints by linearizing the decomposed equations around an LRS background, carrying out a harmonic decomposition, and imposing the cold Magneto Hydrodynamic (MHD) limit with a limited electrical resistivity. The system decouples into two closed and independent subsectors once some harmonic coefficients are solved for in terms of the others. We then examine various methods for producing magnetic field perturbations by numerical calculations, which exhibit certain characteristics like those of earlier research utilising Friedmann-LemaîtreRobertson-Walker (FLRW) backgrounds. Furthermore, due to interference between gravitational waves and plasmonic modes in the short wavelength limit, beat-like patterns are seen.

Keywords

Electromagnetic; Stewart-walker lemma; Perturbations

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S. Mackowski ¹

Affiliations
1 Executive Manager, Journal of Physics and Astronomy,, GB

Abstract

No Abstract

Keywords

No Keywords

Full Text